Air interface backhaul is a common data transmission manner used in a base station in which a baseband and radio frequency are integrated. In a communications system in TDD (time division duplex) mode, without adding a spectrum, an access side and a backhaul side can share a spectrum in TDD in-band relay by adjusting a timeslot.
Currently, the access side (Access Point Base Transceiver Station, AP BTS) and the backhaul side (Backhaul User Equipment, BH UE) of the TDD in-band relay use their respective independent radio frequency channels. Specifically, referring to FIG. 1, an access-side baseband transmit module 101 sends data to an access antenna 103 by using a radio frequency channel 102 corresponding to the access-side baseband transmit module 101, and the access antenna 103 sends the data to a terminal; the access antenna 103 receives the data, and sends the received data to an access-side baseband receive module 104 by using the corresponding radio frequency channel 102. Similarly, a backhaul-side baseband transmit module 105 sends data to a backhaul antenna 107 by using a radio frequency channel 106 corresponding to the backhaul-side baseband transmit module 105, and therefore the backhaul antenna 107 sends the data to the terminal; the backhaul antenna 107 receives backhaul data and sends the received backhaul data to a backhaul-side baseband receive module 108 by using the radio frequency channel 106.
During implementation of the present invention, the inventor finds that the existing solutions at least have the following problems:
Both a radio frequency channel on an access side and a radio frequency channel on a backhaul side can implement a same function, and therefore resource utilization of a radio frequency channel in the foregoing system is relatively low. In addition, because the access side and the backhaul side use their respective independent radio frequency channels, and each radio frequency channel includes multiple components, development costs of the foregoing system are relatively high.